A. Field Of The Invention
The present invention relates to wringers for use in clean rooms, and particularly to a versatile, wringer that can wring a variety of types and sizes of mops, wipes, sponges and other wringable materials without use of lubricating oils and greases.
B. Related Art
Certain pharmaceuticals, electronics and other specialized goods must be manufactured in contamination-free "clean rooms" which are kept free from impurities such as dust and microorganisms. Similarly, hospitals maintain their operating rooms as "clean rooms" in which all reusable items are sterilized in high-heat autoclaves prior to reuse.
As a usual aspect of maintaining the contamination-free environment of a clean room, a cleaning crew typically comes through on a regular basis with a bucket of cleaning solution, a mop, a wringer and sponges. The crew mops up the entire floor, wringing the mop with the wringer whenever it gets dirty. Sponges are usually squeezed out into the bucket of cleaning solution.
It should be noted that the most common type of wringer is the downward gear press wringer. The wringer uses levers, gears and springs to move two parallel bars downward, thereby applying a downward force on the mop head. The mop is supported from below by a perforated pan. However, there are several drawbacks associated with using this mop in a clean room environment.
To begin with, the typical wringer cannot be sterilized in an autoclave. The moving parts of the wringer are normally coated with grease or oil to reduce friction. In the high heat of an autoclave, the grease and/or oil flows very easily and drips onto the autoclave. The wringer then must be re-lubricated before it can be used again.
Grease and oil are problematic in other ways, such as getting into the cleaning solution and eventually onto the floor and walls of the clean room. Unfortunately, to do away with the lubricant allows moving metal parts such as shafts to directly contact adjoining metal surfaces, creating metal particles which drop down into the cleaning solution.
Aside from introducing new contaminants into the clean room, these wringers have other operational difficulties. First, the normal wringer is not versatile. It is designed for a certain type and size of mop, and cannot accept other shapes and sizes of mops. So, for instance, a large, square sponge mop may not fit into a wringer designed for a small string mops. Even when a wringer accepts more than one type of mop, its water-extracting performance is generally much better for one type of mop than another.
Second, a wringer will generally not apply even wringing pressure to wringable items. For instance, a downward gear press wringer will typically apply substantial pressure to limited areas of the mop, but not apply any pressure to other areas. Consequently, the wringer does not wring water from certain portions of the mop.
Third, typical wringers are difficult to clean. Dirt particles get caught in the cracks and corners of the assembly, which must then be hosed down. If the wringer is not regularly cleaned, accumulating dust and dirt fall down into the cleaning solution and work their way back onto surfaces of the clean room.
Additionally, most wringers have a minimum item size because the gear press will only travel so far. Accordingly, the wringers will not clean small wipes or sponges.